The ball moves the same horizontal distance in the equal time intervals because no horizontal component of force is acting on it.
{"Image DocumentName": "5.5 Projectiles Launched Horizontally", "Image ImageDescription": "There are two important things to notice in the photo of two balls falling simultaneously: The ball\u2019s horizontal component of motion remains constant. Gravity acts only downward, so the only acceleration of the ball is downward. Both balls fall the same vertical distance in the same time. The vertical distance fallen has nothing to do with the horizontal component of motion.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}